1. Field of the Invention
The present invention relates to hinges and more particularly, to such a hinge, which uses two reversed cam wheel components to achieve auto-return and auto-turning functions.
2. Description of the Related Art
A consumer electronic product with a lifting cover such as mobile computer, electronic dictionary, mobile video player, cell phone, etc., commonly uses a hinge to coupled the cover to the base member so that the cover can be opened from or closed on the base member. Therefore, the hinge also determines the quality level of the product. A good hinge allows positive positioning and must have means to limit the turning angle.
Following the development of live communication software with video transmission function, such as MSM Messenger, digital image pickup devices, such as web cam or PC cam and etc., have become popular. A web cam is connected to a personal computer through a COM.Port or USB so that the computer can transmit the images picked up by the web cam to other users through a network. Without the computer, the web cam cannot work. A mobile web cam can also be connected to a mobile computer for video communication. However, a mobile web cam is not the standard equipment of a mobile computer. A mobile computer user cannot make a video transmission without a web cam. There are manufacturers who provide mobile computers with built-in web cam, i.e., the web cam is mounted on the mid point of the top side of the display screen of the cover member of the mobile computer by means of a hinge. By means of the hinge, the web cam can be turned relative to the cover member to different angles. However, this design does not provide an auto-return function or auto-turning function within a certain angle. Further, when the web cam is turned over 180°, causing it to return picked up images to normal position when turned through 180°, the picked up images are reversed, bringing inconvenience to the user.